Whilst the actual novel does not directly address the fact of imperialism, this is only because it is an assumed reality of the world that is presented to the reader in this novel. Nonetheless Quatermain's narrative challenges the assumption that the British, because of their supposedly greater skill, intellilgence and moral virtue, are beholden to bring the light of civilisation to "darker" areas of the world, such as Africa.
[A]m I a gentleman? What is a gentleman? I don't quite know, and yet I have had to do with niggers—no, I will scratch out that word "niggers," for I do not like it. I've known natives who are, and so you will say, Harry, my boy, before you have done with this tale, and I have known mean whites with lots of money and fresh out from [England], too, who are not.
Yet the novel does illustrate the complexity of imperialist ideologies and understandings, even in someone who challenges imperialism. For instance, the way in which Quatermain talks to the various non-white characters gives evidence of this belief of European superiority that was at the heart of British imperialism. Note how this supremacy is expressed in the following response of Umbopa to Quartermain's reprimand that he remember his station:
"How dost thou know that I am not the equal of the Inkosi I serve?" he said. "He is of a royal house, no doubt; one can see it in his size and in his eye; so, mayhap, am I. At least I am as great a man."
Such a comment draws the reader's attention to the notion of in/equalitity in the novel, which was at the heart of British imperialism.
Note, too, how Ignosi's isolationist policy when he gains the throne is designed to try and curtail the spread of the more negative impacts of imperialism: violence, greed and drunkenness. While Haggard clearly shows he recognises the dark and ugly side of imperialism, the way in which Quatermain treats various non-white characters also shows that the basic myth of white supremacy is a complexity that was not at that time in history amply sorted out in the minds of Westerners.